题解 | #小美走公路#

分往左走和往右走两种情况讨论即可，输出可以用前缀和优化至o(1)。

#include<bits/stdc++.h>
#define int long long
#define double long double
#define x first
#define y second
using namespace std;
typedef long long LL;
typedef long long ll;
typedef pair<int, int> PII;
const int N = 3e5 + 10;
const int M = 1e3 + 10;
int mod = 1e9 + 7;
int a[N];

void solve() {
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i], a[i] += a[i - 1];
    int x, y;
    cin >> x >> y;
    if (x > y) swap(x, y);
    int ans = min(a[y - 1] - a[x - 1], a[x - 1] + a[n] - a[y - 1]);
    cout << ans << "\n";

}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    int _;
    _ = 1;
    //cin>>_;
    while (_--) {
        solve();
    }
}